Web Services can make your applications Web applications.

Web Services are published, found and used through the Web.

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What You Should Already Know

Before you continue you should have a basic understanding of the following:

• HTML
• XML

If you want to study these subjects first, find the tutorials on our Home page.

What is Web Services?

• Web services are application components
• Web services communicates using open protocols
• Web services are self-contained and self-describing
• Web services can be discovered using UDDI
• Web services can be used by other applications
• XML is the basis for Web services

How Does it Work?

The basic Web services platform is XML plus HTTP.

The HTTP protocol is the most used Internet protocol.

XML provides a language which can be used between different platforms and programming languages and still express complex messages and functions.

Web services platform elements

• SOAP (Simple Object Access Protocol)
• UDDI (Universal Description, Discovery and Integration)
• WSDL (Web Services Description Language)

We will explain these topics later in the tutorial

The Future of Web services

Don't expect too much too soon.

The Web Services platform is a simple, interoperable, messaging framework. It still misses many important features like security and routing. But, these pieces will come once SOAP becomes more advanced.

Hopefully Web services, or something like it, can make it much easier for applications to communicate. 

A web service is typically an application programming interface (API) or Web API that is accessed via Hypertext Transfer Protocol (HTTP) and executed on a remote system, hosting the requested service. Web services tend to fall into one of two camps: big web services and RESTful web services. The W3C defines a "web service" as "a software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically Web Services Description Language WSDL). Other systems interact with the web service in a manner prescribed by its description using SOAP messages, typically conveyed using HTTP with an XML serialization in conjunction with other Web-related standards." The W3C also states, "We can identify two major classes of Web services, REST-compliant Web services, in which the primary purpose of the service is to manipulate XML representations of Web resources using a uniform set of "stateless" operations; and arbitrary Web services, in which the service may expose an arbitrary set of operations.